Cyberpunk 2077 Still Needs An SMT Tweak For Best Performance On 8-Core AMD Ryzen CPUs

cyberpunk2077 rtoverdrive heroimage
Those with a particular interest in the topic may recall that among Cyberpunk 2077's many issues at launch was a major performance problem on AMD Ryzen CPUs where the game wouldn't make use of the extra logical cores afforded by those processors' simultaneous multi-threading (SMT) feature. The game's developer issued an update in December of 2020, numbered version 1.05, that purportedly patched up this problem.

cyberpunk patch105 amd fix note
The patch note from back in December of 2020.

According to the release notes for the update, the fix was developed in cooperation with AMD, and it only applied to four- and six-core Ryzen CPUs because eight-, twelve-, and sixteen-core models were "behaving as intended." We actually tested that notion not long after the patch came out, way back in December 2020, and found that hacking the game executable to enable SMT on 8-core CPUs definitely improved performance.

Despite two years having passed in the interim, it turns out that's still the case. Thanks to a tip on Twitter from the developer of the free and fantastic performance capture tool CapFrameX, we elected to spend the early morning running benchmarks in Cyberpunk 2077 to see if the fabled "AMD Hack" still applies with the current version of the game. Let's take a look at what we found:

cyberpunk2077 5800x3d smt tweak chart

How about that? Each benchmark result here is the aggregate of three tests performed on a fresh launch of the game after changing settings. We tested in 3840⨯2160 resolution, with all in-game settings at their maximum values aside from DLSS, which was manually set to 'Performance' mode.

On our test rig with a Ryzen 7 5800X3D CPU and GeForce RTX 4080 16GB GPU, we saw clear performance gains across the board in a custom test scenario involving a one-minute ride through Night City's busy City Center district at rush hour, when the road is full of cars. Why didn't we use the in-game benchmark, you might ask?

cp2077 builtin benchmark
Cyberpunk 2077's built-in benchmark doesn't hit the CPU very hard at all.

Cyberpunk 2077's in-game benchmark is a fantastic test for GPU prowess, as that's primarily what it targets. However, Cyberpunk can be a surprisingly heavy game on CPUs, particularly when you are driving around busy streets at speed. On the built-in benchmark, we saw a margin-of-error performance difference between whether we used the tweak or not, but in our custom test scenario, it was a bit more noticeable.

Overall, you're going to see the biggest difference when the game is CPU-limited, not GPU-bound, and that's why the largest improvements are in the 1% and 0.1% low values. So saying, this tweak primarily increases smoothness, not maximum performance. You're not going to see your average framerate skyrocket, but it's a really nice bump to your worst-case performance, and it even helps when using the RT Overdrive path-tracing mode, as we noted.

cp2077 cpu utilization
Before and after the tweak. It's heavy stuff.

The cause of this performance difference is drastically-increased CPU utilization. Enabling the tweak took our average total CPU utilization during the benchmark from between 33% and 47% (depending on settings) all the way up to 74%, with peaks at 95%. That's impressively-high CPU utilization for a video game on a 16-thread CPU. That increase in utilization also brought with it a bump in power usage, with package power hitting a peak of 95W—up from 75W without the tweak.

cyberpunk2077 rogally smt tweak chart

Out of curiosity, we also tested the tweak on the ASUS ROG Ally and its Ryzen Z1 Extreme eight-core Zen 4 processor, using the same settings we tested during our review. Unfortunately, it didn't have nearly the same effect. In fact, the effect is basically a margin-of-error difference on the little handheld PC. But why?

We suspect that this basically comes down to the ROG Ally's use of integrated graphics. It's not that the integrated GPU is too slow for to matter—although that's also a factor—but rather, the limiting value on the ROG Ally is actually the SoC's 35W power limit. That limit is shared between CPU cores and GPU; allowing the game engine to make use of all sixteen threads is fine and well, but it doesn't matter if you're slamming against the power limit, and may in fact make things worse by drawing power away from the struggling GPU.

cyberpunk2077 path tracing 1

By the way, Cyberpunk 2077 just got an update to hotfix version 1.63f that included a patch to improve DLSS 3 Frame Generation, specifically on systems with AMD CPUs. In combination with a firmware update for the author's ASRock X570 Taichi motherboard that also was specifically marked to improve compatibility with GeForce RTX 40-series GPUs, DLSS 3 has become an unequivocal recommendation from this reviewer, at least in Cyberpunk. At this point, it offers radically improved performance with no downside whatsoever.

CapFrameX's tweet was actually highlighting the work done researching this topic by German site, and we'd be remiss if we didn't point out that those fellows are trying to crowdsource test data from their users with a specific save game. We didn't use that save game for our testing, but if you'd like to contribute, you can find the download on that page as well as more test data, including with a Ryzen 7 7800X3D that we didn't have on hand for our testing.

So how do you get the fix? You could go about it by manually hex-editing your Cyberpunk 2077 executable; if you're keen on that (and thus keeping your game otherwise-unmodified), there are instructions for how to do so both over at the PCGamesHardware page linked above as well as in English at the PC Gaming Wiki.

cyber engine tweaks screenshot
Make sure you restart the game after clicking "Save".

However, a much more sensible way is to simply install the mod Cyber Engine Tweaks, which you're probably already using anyway. Recent versions of Cyber Engine Tweaks include a checkbox right in the settings menu (pictured above) to toggle the AMD SMT fix. You can find the open-source Cyber Engine Tweaks mod right over here on GitHub.